Description: As in the original application, Core D will provide the histological and technical support for quantitative assessment of anatomical structures utilizing unbiased, design-based stereological techniques. Utilization of unbiased stereological counting methods will allow the investigators to ascertain accurate, quantitative data with mathematically sound methodologies. The Core will use a microscope linked with a computer and automatic stage designed to allow for optimal utilization of stereological principles to quantify parameters such as brain regional volume, cell or synapse number, and neuronal process density/length and how these parameters are modified by hypoxia-ischemia. The Core will assist in tissue processing as well as in stereological analysis.